Audiobus: Use your music apps together.
What is Audiobus? — Audiobus is an award-winning music app for iPhone and iPad which lets you use your other music apps together. Chain effects on your favourite synth, run the output of apps or Audio Units into an app like GarageBand or Loopy, or select a different audio interface output for each app. Route MIDI between apps — drive a synth from a MIDI sequencer, or add an arpeggiator to your MIDI keyboard — or sync with your external MIDI gear. And control your entire setup from a MIDI controller.Download on the App Store
Audiobus is the app that makes the rest of your setup better.
OT: bargain alert - Sennheiser Ambeo Headset, great field recorder on firesale
Just a heads-up, I think these are on the verge of being discontinued. They originally retailed for £275 and can be found on Amazon UK for just £39.
I've had a pair for the past year and if you own an iPhone they're terrific for field recordings - you can record straight into Audioshare with great quality. They're binaural and are equipped with an Apogee preamp.
Here's a sample I recorded last year, a woodpecker in a local park:
They're also discounted in the US, but not by as much: